config: Move integration/* back to #wikimedia-dev

Follows-up Idbb0befe124c which removed the duplicate feed for
QA projects from #wikimedia-dev, but also moved integration/*.

These are now back in #wikimedia-dev.

Leaving the mirror of integration/* in #wikimedia-qa, can be
turned off there however if QA channel prefers not to have them.

Change-Id: Id6a8d91e49d7a6f93cfdbcdeb44744af60867c92